They all have watched enough Gundam shows over the years to have seen it all. The rest is up to imagination. That they can name systems and techniques doesn't mean they necessarily know how they were achieved. In fact I kind of doubt great many gunpla builders know it themselves. It must be at least half trial and error. Use some fancy material/coating, then see how the game board (Plavsky particles) react to it. Of course over time you'd start to learn enough to be able to predict a little and connect some dots. Especially if you have a whole research team working on it, like Nemesis or Kawaguchi has, for example. Although it's a different thing to operate a gunpla and build it. You could be a master operator without knowing anything about building or theory, as long as you were sharp enough to recognize your own gunpla's potential as well as the enemy's. Reiji was like that, and Sekai is now. Aila might have become an exceptional builder, not only an operator, because she could see the particles. She would have immediately seen with her own eyes if some material was promising.